The impact of piler-radiation on the growth rate of opportunistic microorganisms

Abstract

The spread of resistant to antimicrobial agents strains of opportunistic microorganisms causes the search for new ways of struggle with them. Among these ways, special attention is drawn to the use of physical factors, in particular, different types of radiation, with potential antimicrobial activity. Purpose: to investigate the direct effect of the PILER wave length line on the growth rate of S.aureus ATCC 25923 and P.aeruginosa ATCC 27853 on solid nutrient media. The influence of PILER (Polarized Polychromatic Incoherent Low Energy Radiation) on various wavelengths on the growth intensity of the collection test- strains of S.aureus ATCC 25923 and P.aeruginosa ATCC 27853 on solid nonselective nutrient media (NA) was investigated. The results were determined by counting the number of bacterial colonies on the dishes and compared with control – similar unirradiated cultures. The effect of PILER of different wavelengths and exposures (5, 10, 15 and 20 min) was investigated by separate series. PILER light source – Med All Bioptron light therapy system by Zepter Group. The obtained results testify to the significant influence of PILER radiation on the intensity of the growth of research objects. The degree of influence depended on the duration of irradiation and showed insignificant stimulation of the growth of bacteria in 5–10-minute exposures and expressed bactericidal and bacteriostatic effect at exposure for 20 minutes. The 20-minute exposure PILER on the S.aureus 25923 strain resulted in a decrease of the number of bacterial colonies by 37–65% compared to control, P.aeruginosa 27853 – by 58–81% compared to control. PILER has a significant modulator effect on the growth of the examined conditionally pathogenic microorganisms on solid nutrient media. The degree of this effect depends on the radiation parameters, in particular on the dose density and the wavelength of light, and at exposures of 20 minutes is manifested in marked bactericidal and bacteriostatic effects on microorganisms.